Swapping in a wider axle -- Pls help

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SquareKraut

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Hi all,
I've got a 1990 R1500 Suburban, 350 / 700R4 / 10 bolt with 3.73 factory posi.

As far as I know, that's pretty much a regular C10 setup, with 63.5" axle width WMS-WMS.

What I'd like to achieve is a massive increase in axle width, and be closer to 70" width, even 72" is OK.
I don't care about how many lugs I end up with,
I don't care about what brakes the new axle comes with,
I don't care for the new axle to be beefier / heavier, but won't be opposed

What are my donor truck choices for a wider rear axle?
OBS 4x4 is wider than mine, correct?
NBS, and NNBS are each a little wider than that?

What will be the least amount of headache to adapt?
I'm guessing that leaf spring mounts and shock mounts will need to be relocated, but hoping to match up to my drive shaft at least.

Thank you for any advice at all!
 

Frankenchevy

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Rockwells are 69.5”

They’d be interesting on a 2wd half ton

edit: I think you’d be better off with spacers and wheel offset though.
 

nvrenuf

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The D70HD from a square body dually pick up (not a cab & chassis) is 74” wide.
 

Bennyt

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What are you trying to achieve with a wider axle?

Some of the 70-80's vans have a wider axle that matches the 4wd front axle width. I believe it is 2" wider, only on the 14b FF, and should bolt in. I got one years ago when I was building my K5 to match the front Dana but ended up not using it but I am pretty sure the perch widths were the same. Still not going to get you to the width you are looking for.
 

SquareKraut

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The only bummer about 1 ton axles is the increased drive train loss, which I'm guessing is noticeable.
I've got very little power from the stock TBI.
It would be awesome if there were a newer axle from a 1500 or 2500 that could be swapped in and require only spring and shock mount relocation.
I'm just not sure about yoke location, and drive shaft compatibility, etc.

The reason I want to do it is because the front is getting widened via extended control arms, but I need to know how wide I can go in the rear without spacers first, because that dictates the setup for the front. I want front and rear to end up square, not staggered like from the factory.
The Method wheels I want to run don't come in extreme offsets, and I don't want to run some extreme spacer. 1" or 2" spacer if necessary is fine, but no more.

Thanks for any input!!
 

Frankenchevy

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You can get Ford 9” or maybe a lighter Dana tubed in any width you want. Always an option...
 

bucket

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An '88-'98 1/2 ton 4x4 will have a wider rear axle. I don't remember exactly how wide, but I think it's around 67-69 wms-wms.
 

fast68chevy

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as far as wider 8.5 or 12 bolt axles go .,. the G series van ones. or ';88-up new body style pickups burbs etc. are your options. if you get G20 one then youll have the wider 2-3/4" wide brakes, as you will with the F44 HD chassis C1500 pickups burbs too. both are very common.
 

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